The diagram shows an isolated, positive
charge Q, where point B is twice as far away
from Q as point A.
+Q ____A____ B
0 10cm 20cm
What is the ratio of the electric field
strength at point A to the electric field
strength at point B?
Draw a convex quadrilateral ABCD, where the diagonals intersect
at point M. Prove: If ABCD is a parallelogram, then M is the
midpoint of each diagonal.
*(4) (a) Prove that if p=(x,y) is in the set where y<x and if
r=distance from p to the line y=x then the ball about p of radius r
does not intersect with the line y=x.
(b) Prove that the set where y<c is an open set.
Justify your answer
Problem 2. Give an example of an open set
O such that the boundary of the closure of O has
positive Lebesque measure. (Hint: try to play with
the union of open intervals taken out of [0, 1] during the
construction of Cantor set on... ODD steps.)
2. (a) Prove that U45 is generated by the set {14,28}.
(b) Prove that the additive group Z×Z is generated by the set
S={(3,1),(−2,−1),(4,3)}.
Please be thorough step by step with details, please.